What is the proper terminology?

[dhkaiser]

Is using a JL Chute Release on a single separation rocket a dual deploy? Or would one call it a delayed deploy? Or something else? If dual deploy would it be accepted for a L3 cert? Not intending to do that as I am L1 just curious.

edit: spelling

 

[mikec]

It's "dual", not "duel".

You can't use a Chute Release for L3 because it uses motor eject for apogee and the requirements are for electronic deployment at apogee (even if there were any L3 motor that had motor eject, which AFAIK there isn't.)

You can call the Chute Release "dual deploy" if you want to, there are no official standards for terminology. At this point I'd just call it "using a Chute Release" as there is no term I'm aware of for tethering of the main, either pyro or non-pyro-based, though such products have been around for years.

The phrase "dual deployment" is a trademark of Adept Rocketry, at least according to them. IANAL but the term seems to have become as generic as "kleenex".

 

[Steve Shannon]

Is using a JL Chute Release on a single separation rocket a duel deploy? Or would one call it a delayed deploy? Or something else? If duel deploy would it be accepted for a L3 cert? Not intending to do that as I am L1 just curious.

If you're doing something at apogee to break the rocket apart so it's not screaming down, even if it doesn't have a drogue chute or streamer, that's your first "deployment". When the chute release releases your main at a lower altitude that's a second deployment. In my opinion I would consider it dual deployment.

Dual deployment is not required for L3 certification. Redundancy is required.

I don't know why the chute release could not be used for L3. Redundancy could be done by connecting them to each other. You'd need another set of electronics for the apogee event.

Steve Shannon

 

[LW Bercini]

Around here, people refer to it as "teathered"

 

[K'Tesh]

If you're doing something at apogee to break the rocket apart so it's not screaming down, even if it doesn't have a drogue chute or streamer, that's your first "deployment". When the chute release releases your main at a lower altitude that's a second deployment. In my opinion I would consider it dual deployment.

Dual deployment is not required for L3 certification. Redundancy is required.

I don't know why the chute release could not be used for L3. Redundancy could be done by connecting them to each other. You'd need another set of electronics for the apogee event.

Steve Shannon

For a L3, wouldn't the "another set of electronics" need a redundancy as well? Either a motor ejection or 2nd flight computer to make sure that everything separates properly?

 

[dhbarr]

Two altis to pop the top, two JLCR's to unfurl the reefing.

I would think any L3 review would pass that.

 

[Steve Shannon]

For a L3, wouldn't the "another set of electronics" need a redundancy as well? Either a motor ejection or 2nd flight computer to make sure that everything separates properly?

Yes, that's right. You need redundancy for everything that deploys a parachute. Motor ejection is allowed by NAR for the redundant system, but as MikeC said earlier, good luck finding an M, N, or O motor with ejection.

 

[Steve Shannon]

Two altis to pop the top, two JLCR's to unfurl the reefing.

I would think any L3 review would pass that.

I agree. I would.

 

[Buckeye]

The recovery process is in two steps, so yes, it counts as "dual" deploy in my book.

 

[MikeyDSlagle]

It's "dual", not "duel".

You can't use a Chute Release for L3 because it uses motor eject for apogee and the requirements are for electronic deployment at apogee (even if there were any L3 motor that had motor eject, which AFAIK there isn't.)

You can call the Chute Release "dual deploy" if you want to, there are no official standards for terminology. At this point I'd just call it "using a Chute Release" as there is no term I'm aware of for tethering of the main, either pyro or non-pyro-based, though such products have been around for years.

The phrase "dual deployment" is a trademark of Adept Rocketry, at least according to them. IANAL but the term seems to have become as generic as "kleenex".

The JLCR doesn't require motor eject. It just needs something to get it out of the rocket. Be that motor deploy or electronic controlled separation/deploy at apogee. Motor eject does seem to be the most popular.

Mikey D

 

[Nytrunner]

At the L3 level, Its probably cheaper just to go with the dual-deploy altimeters.
2 chute releases adds ~250$ to an already expensive rocket.

A tender-descender is another less expensive option for single bay deployment. (still two events)

 

[rharshberger]

L3 electronic deployment does not mean dual deploy only. Electronic pop at the top is acceptable as well.

 

[John Beans]

I'm hoping in the future we can do away with explosive charges entirely.

 

[tim cubbedge]

I'm hoping in the future we can do away with explosive charges entirely.

I hope we never do!

 

[John Beans]

I hope we never do!

Aren't you tired of black gunk all over everything, and burned chutes?
Baffles and blankets and dog barf? (oh my)

Also: safety, ATF.

 

[tim cubbedge]

Aren't you tired of black gunk all over everything, and burned chutes?
Baffles and blankets and dog barf? (oh my)

Also: safety, ATF.

Nah, I love the pyrotechnics involved!
Knock on wood but never burned a chute 😃

 

[BDB]

I'm hoping in the future we can do away with explosive charges entirely.

I'm listening.....

 

[MikeyDSlagle]

I'm hoping in the future we can do away with explosive charges entirely.

As am I. I've no problem with pyro charges. But if there is a cleaner way... I will certainly be listening.

 

[John Beans]

I think modularity is a good thing. You know how you can move Chute Release from rocket to rocket, instead of "building it in" to each rocket? And you can loan it to someone, or add it to a rocket you've already been flying for a year? As opposed to building a sled, screwing down an altimeter, running wires through bulkheads, and "installing" all that stuff in a way that takes some time and effort to share among rockets. Modularity is when you can take a part from one rocket and easily move it to another. Or replace a broken part. Or upgrade a part.

I think everything about a rocket should be as modular as possible, including fins and recovery equipment.

I think you should be able to build a booster section, with replaceable fins and swap-able engine adapters.

And I think there should be something called a recovery section that should be movable from rocket to rocket. And that recovery section would include all the electronics that it requires to operate. So, for instance, you could have a 2.56" diameter recovery section that you could just move from rocket to rocket. If you had a 38mm booster section, you could use an a 38mm-2.56" transition section, and the rocket would look like an Honest John / Estes Ventris. So you'd take a booster section, add a recovery section, add a nosecone (snap on, screw on, fasten shock cords). You'd need to weigh and balance your final configuration, but a simple app could check your stability.

And I think if you break something (or want to upgrade something), you should be able to just add that to existing rockets.

If you wanted to add two recovery sections to a rocket for some reason, that would be easy. Or three.

The recovery section could include camera bay for key chain cameras. And while it's at it, the recovery section (which has to have a built in altimeter to work) could also collect data and wirelessly connect to your smart phone. A *really* good recovery section would also include built-in wireless tracking so that you could locate it.

And though it all sounds super fancy, I think it would be much more reliable and safe than how we do it today. We have the technology!

 

[Nytrunner]

I think modularity is a good thing. You know how you can move Chute Release from rocket to rocket, instead of "building it in" to each rocket? And you can loan it to someone, or add it to a rocket you've already been flying for a year? As opposed to building a sled, screwing down an altimeter, running wires through bulkheads, and "installing" all that stuff in a way that takes some time and effort to share among rockets. Modularity is when you can take a part from one rocket and easily move it to another. Or replace a broken part. Or upgrade a part.

I think everything about a rocket should be as modular as possible, including fins and recovery equipment.

I think you should be able to build a booster section, with replaceable fins and swap-able engine adapters.

And I think there should be something called a recovery section that should be movable from rocket to rocket. And that recovery section would include all the electronics that it requires to operate. So, for instance, you could have a 2.56" diameter recovery section that you could just move from rocket to rocket. If you had a 38mm booster section, you could use an a 38mm-2.56" transition section, and the rocket would look like an Honest John / Estes Ventris. So you'd take a booster section, add a recovery section, add a nosecone (snap on, screw on, fasten shock cords). You'd need to weigh and balance your final configuration, but a simple app could check your stability.

And I think if you break something (or want to upgrade something), you should be able to just add that to existing rockets.

If you wanted to add two recovery sections to a rocket for some reason, that would be easy. Or three.

The recovery section could include camera bay for key chain cameras. And while it's at it, the recovery section (which has to have a built in altimeter to work) could also collect data and wirelessly connect to your smart phone. A *really* good recovery section would also include built-in wireless tracking so that you could locate it.

And though it all sounds super fancy, I think it would be much more reliable and safe than how we do it today. We have the technology!

Modularity is a fantastic idea. I love removable fasteners and rivets just from a convenient-access standpoint, but if a builder standardizes their hole patterns to allow component compatibility, that could reduce flight prep time greatly!

Wasn't there a PMW kit that claimed to be flyable in 6 configurations? From Simple motor deploy to full dual-ejection?

 

[Handeman]

I think modularity is a good thing. You know how you can move Chute Release from rocket to rocket, instead of "building it in" to each rocket? And you can loan it to someone, or add it to a rocket you've already been flying for a year? As opposed to building a sled, screwing down an altimeter, running wires through bulkheads, and "installing" all that stuff in a way that takes some time and effort to share among rockets. Modularity is when you can take a part from one rocket and easily move it to another. Or replace a broken part. Or upgrade a part.

I think everything about a rocket should be as modular as possible, including fins and recovery equipment.

I think you should be able to build a booster section, with replaceable fins and swap-able engine adapters.

And I think there should be something called a recovery section that should be movable from rocket to rocket. And that recovery section would include all the electronics that it requires to operate. So, for instance, you could have a 2.56" diameter recovery section that you could just move from rocket to rocket. If you had a 38mm booster section, you could use an a 38mm-2.56" transition section, and the rocket would look like an Honest John / Estes Ventris. So you'd take a booster section, add a recovery section, add a nosecone (snap on, screw on, fasten shock cords). You'd need to weigh and balance your final configuration, but a simple app could check your stability.

And I think if you break something (or want to upgrade something), you should be able to just add that to existing rockets.

If you wanted to add two recovery sections to a rocket for some reason, that would be easy. Or three.

The recovery section could include camera bay for key chain cameras. And while it's at it, the recovery section (which has to have a built in altimeter to work) could also collect data and wirelessly connect to your smart phone. A *really* good recovery section would also include built-in wireless tracking so that you could locate it.

And though it all sounds super fancy, I think it would be much more reliable and safe than how we do it today. We have the technology!

That all sounds great. Kind of like the 2017 cars that are out with all the electronics, self driving, etc. You just hop in and go, you don't really have to drive them, not like you did back in the day.

The modular rockets sounds like a simple and efficient way to get something to fly and recover. Something that could be mass produced and work every time. Kind of like buying Estes RTF or ATF models.

The problem is I'm into the rockets for the same reason I like old carbureted hot rods and muscle cars that you had to hop up, tune up, and build yourself and actually drive. I like designing, building, wiring, sewing chutes and cords, and all the other things that go into building the rocket from the ground up. If rockets ever get to be all modular and are just a matter of swapping pre-made parts and electronics around, I think I'll find another hobby.

for the OP, I don't think there is any proper terminology yet. Give it 6 months or a year and I think you'll see people will gravitate to terms where most people will know what you are talking about and the allowed/not allowed will be worked out. It's getting there but needs some more time.

 

[dhbarr]

I propose "baby unfurl the reefer" :-D. I hope you all get that stuck in your head everytime you see or use one.

In all seriousness, I've been thinking of it as 1.5D, deploy-and-a-half.